However, whether or not it's a good interpretation depends on the details of how the film plays out. If the dwarves are made aware of Bilbo's personality, or of the habits of hobbits, before they ever show up at Bag End, then the contract will make a lot of sense, as it will be "aping" the hobbit style. But if it is portrayed as a "dwarvish" contract, then it will simply be a misinterpretation of the source material. And IMO, a serious one. It will not ruin the film for me, but it will be a missed opportunity to really get this one right.